code: def categories(self):
      if self._categories is None:
          self._categories = {
              "categories": self.meta_data["categories"],
              "feature_names_categorical": self.meta_data[
                  "feature_names_categorical"
              ],
          }
      return self._categories
  
imports: import numpy
  import os
  import json
  import h5py
  from tqdm import tqdm
  from torchmeta.utils.data import Dataset, ClassDataset, CombinationMetaDataset
  from torchmeta.datasets.utils import get_asset
label_desc: Use image node_id 8 for calling the BachClassDataset obj's underlying member method code with example usage: obj.categories() and returns: self